39
Figure 34: Minimum Piping Requirements For Gravity Return Series 24 Steam Boilers
NOTES:
1. All piping is schedule 40.
2. To prevent condensate from being trapped in header, do not reduce
equalizer elbow at header connection.
3. Ball valve preferable, gate valve acceptable alternative
(supplied by others).
• Minimum valve size per ASME code is 3/4” NPT 24-03/24-04;
1” NPT 24-05/24-08; 1-1/4” NPT 24-09/24-12.
• Increasing the valve size will improve the blowdown operation.
• In all cases, piping connecting blowoff valve to boiler shall be full
size to the point of discharge.
4. Header piping may be run over top of the boiler if space does not
allow for piping arrangement shown. Increased service
requirements will result however.
5. Supply from the boiler header must be connected between the first
boiler riser and the header drip (or Hartford Loop). Do not connect
supply between risers or opposite end of boiler header.